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[PMID]: 28574569
[Au] Autor:Liu F; Lakey PSJ; Berkemeier T; Tong H; Kunert AT; Meusel H; Cheng Y; Su H; Fröhlich-Nowoisky J; Lai S; Weller MG; Shiraiwa M; Pöschl U; Kampf CJ
[Ad] Address:Multiphase Chemistry Department, Max Planck Institute for Chemistry, Hahn-Meitner-Weg 1, 55128 Mainz, Germany.
[Ti] Title:Atmospheric protein chemistry influenced by anthropogenic air pollutants: nitration and oligomerization upon exposure to ozone and nitrogen dioxide.
[So] Source:Faraday Discuss;, 2017 Jun 02.
[Is] ISSN:1359-6640
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:The allergenic potential of airborne proteins may be enhanced via post-translational modification induced by air pollutants like ozone (O ) and nitrogen dioxide (NO ). The molecular mechanisms and kinetics of the chemical modifications that enhance the allergenicity of proteins, however, are still not fully understood. Here, protein tyrosine nitration and oligomerization upon simultaneous exposure of O and NO were studied in coated-wall flow-tube and bulk solution experiments under varying atmospherically relevant conditions (5-200 ppb O , 5-200 ppb NO , 45-96% RH), using bovine serum albumin as a model protein. Generally, more tyrosine residues were found to react via the nitration pathway than via the oligomerization pathway. Depending on reaction conditions, oligomer mass fractions and nitration degrees were in the ranges of 2.5-25% and 0.5-7%, respectively. The experimental results were well reproduced by the kinetic multilayer model of aerosol surface and bulk chemistry (KM-SUB). The extent of nitration and oligomerization strongly depends on relative humidity (RH) due to moisture-induced phase transition of proteins, highlighting the importance of cloud processing conditions for accelerated protein chemistry. Dimeric and nitrated species were major products in the liquid phase, while protein oligomerization was observed to a greater extent for the solid and semi-solid phase states of proteins. Our results show that the rate of both processes was sensitive towards ambient ozone concentration, but rather insensitive towards different NO levels. An increase of tropospheric ozone concentrations in the Anthropocene may thus promote pro-allergic protein modifications and contribute to the observed increase of allergies over the past decades.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1706
[Cu] Class update date: 170602
[Lr] Last revision date:170602
[St] Status:Publisher
[do] DOI:10.1039/c7fd00005g

  2 / 306246 MEDLINE  
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[PMID]: 28574563
[Au] Autor:Tong H; Lakey PSJ; Arangio AM; Socorro J; Kampf CJ; Berkemeier T; Brune WH; Pöschl U; Shiraiwa M
[Ad] Address:Multiphase Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany. h.tong@mpic.de.
[Ti] Title:Reactive oxygen species formed in aqueous mixtures of secondary organic aerosols and mineral dust influencing cloud chemistry and public health in the Anthropocene.
[So] Source:Faraday Discuss;, 2017 Jun 02.
[Is] ISSN:1359-6640
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:Mineral dust and secondary organic aerosols (SOA) account for a major fraction of atmospheric particulate matter, affecting climate, air quality and public health. How mineral dust interacts with SOA to influence cloud chemistry and public health, however, is not well understood. Here, we investigated the formation of reactive oxygen species (ROS), which are key species of atmospheric and physiological chemistry, in aqueous mixtures of SOA and mineral dust by applying electron paramagnetic resonance (EPR) spectrometry in combination with a spin-trapping technique, liquid chromatography-tandem mass spectrometry (LC-MS/MS), and a kinetic model. We found that substantial amounts of ROS including OH, superoxide as well as carbon- and oxygen-centred organic radicals can be formed in aqueous mixtures of isoprene, α-pinene, naphthalene SOA and various kinds of mineral dust (ripidolite, montmorillonite, kaolinite, palygorskite, and Saharan dust). The molar yields of total radicals were ∼0.02-0.5% at 295 K, which showed higher values at 310 K, upon 254 nm UV exposure, and under low pH (<3) conditions. ROS formation can be explained by the decomposition of organic hydroperoxides, which are a prominent fraction of SOA, through interactions with water and Fenton-like reactions with dissolved transition metal ions. Our findings imply that the chemical reactivity and aging of SOA particles can be enhanced upon interaction with mineral dust in deliquesced particles or cloud/fog droplets. SOA decomposition could be comparably important to the classical Fenton reaction of H O with Fe and that SOA can be the main source of OH radicals in aqueous droplets at low concentrations of H O and Fe . In the human respiratory tract, the inhalation and deposition of SOA and mineral dust can also lead to the release of ROS, which may contribute to oxidative stress and play an important role in the adverse health effects of atmospheric aerosols in the Anthropocene.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1706
[Cu] Class update date: 170602
[Lr] Last revision date:170602
[St] Status:Publisher
[do] DOI:10.1039/c7fd00023e

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[PMID]: 28574551
[Au] Autor:Petzold A; Krämer M; Neis P; Rolf C; Rohs S; Berkes F; Smit HGJ; Gallagher M; Beswick K; Lloyd G; Baumgardner D; Spichtinger P; Nédélec P; Ebert V; Buchholz B; Riese M; Wahner A
[Ad] Address:Forschungszentrum Jülich, IEK-8 Troposphere, Jülich, Germany. a.petzold@fz-juelich.de.
[Ti] Title:Upper tropospheric water vapour and its interaction with cirrus clouds as seen from IAGOS long-term routine in situ observations.
[So] Source:Faraday Discuss;, 2017 Jun 02.
[Is] ISSN:1359-6640
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:IAGOS (In-service Aircraft for a Global Observing System) performs long-term routine in situ observations of atmospheric chemical composition (O , CO, NO , NO , CO , CH ), water vapour, aerosols, clouds, and temperature on a global scale by operating compact instruments on board of passenger aircraft. The unique characteristics of the IAGOS data set originate from the global scale sampling on air traffic routes with similar instrumentation such that the observations are truly comparable and well suited for atmospheric research on a statistical basis. Here, we present the analysis of 15 months of simultaneous observations of relative humidity with respect to ice (RH ) and ice crystal number concentration in cirrus (N ) from July 2014 to October 2015. The joint data set of 360 hours of RH -N observations in the global upper troposphere and tropopause region is analysed with respect to the in-cloud distribution of RH and related cirrus properties. The majority of the observed cirrus is thin with N < 0.1 cm . The respective fractions of all cloud observations range from 90% over the mid-latitude North Atlantic Ocean and the Eurasian Continent to 67% over the subtropical and tropical Pacific Ocean. The in-cloud RH distributions do not depend on the geographical region of sampling. Types of cirrus origin (in situ origin, liquid origin) are inferred for different N regimes and geographical regions. Most importantly, we found that in-cloud RH shows a strong correlation to N with slightly supersaturated dynamic equilibrium RH associated with higher N values in stronger updrafts.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1706
[Cu] Class update date: 170602
[Lr] Last revision date:170602
[St] Status:Publisher
[do] DOI:10.1039/c7fd00006e

  4 / 306246 MEDLINE  
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[PMID]: 28574459
[Au] Autor:Baù M; Ferrari M; Ferrari V
[Ad] Address:Department of Information Engineering, University of Brescia, Via Branze 38, Brescia 25123, Italy. marco.bau@unibs.it.
[Ti] Title:Analysis and Validation of Contactless Time-Gated Interrogation Technique for Quartz Resonator Sensors.
[So] Source:Sensors (Basel);17(6), 2017 Jun 02.
[Is] ISSN:1424-8220
[Cp] Country of publication:Switzerland
[La] Language:eng
[Ab] Abstract:A technique for contactless electromagnetic interrogation of AT-cut quartz piezoelectric resonator sensors is proposed based on a primary coil electromagnetically air-coupled to a secondary coil connected to the electrodes of the resonator. The interrogation technique periodically switches between interleaved excitation and detection phases. During the excitation phase, the resonator is set into vibration by a driving voltage applied to the primary coil, whereas in the detection phase, the excitation signal is turned off and the transient decaying response of the resonator is sensed without contact by measuring the voltage induced back across the primary coil. This approach ensures that the readout frequency of the sensor signal is to a first order approximation independent of the interrogation distance between the primary and secondary coils. A detailed theoretical analysis of the interrogation principle based on a lumped-element equivalent circuit is presented. The analysis has been experimentally validated on a 4.432 MHz AT-cut quartz crystal resonator, demonstrating the accurate readout of the series resonant frequency and quality factor over an interrogation distance of up to 2 cm. As an application, the technique has been applied to the measurement of liquid microdroplets deposited on a 4.8 MHz AT-cut quartz crystal. More generally, the proposed technique can be exploited for the measurement of any physical or chemical quantities affecting the resonant response of quartz resonator sensors.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1706
[Cu] Class update date: 170602
[Lr] Last revision date:170602
[St] Status:In-Data-Review

  5 / 306246 MEDLINE  
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[PMID]: 28574394
[Au] Autor:Vepkhvadze N; Kiladze N; Khorbaladze M; Kochoradze T; Kugoti I
[Ad] Address:Tbilisi State Medical University, Department of Preventive Medicine and Environmental Health, Georgia.
[Ti] Title:IMPACT OF SULPHUR DIOXIDE ON THE RESPIRATORY SYSTEM OF TBILISI POPULATION.
[So] Source:Georgian Med News;(265):1114-119, 2017 Apr.
[Is] ISSN:1512-0112
[Cp] Country of publication:Georgia (Republic)
[La] Language:eng
[Ab] Abstract:The possible relationship between levels of sulphur dioxide (SO2) in the air and the rate of respiratory diseases has been studied. Results of monitoring of main contaminants of outdoor air were analyzed and they are reflected in Environmental Report 2015. Information on morbidity by respiratory system diseases of Tbilisi population is has been taken from 2011-2015 reports of the National Center of Disease Control. Identified that there is no consistent correlation between sulphur dioxide concentration in the air and respiratory system disease rates in the population, including children. Obtained data demonstrated that during the study period maximum SO2 concentration was registered in 2015 - 0,14 mg/m3 (exceeding almost 3 times maximum permissible concentration - 0,5 mg/m3) and in the same year high morbidity rates are registered (incidence -18106,08), though the lowest rates are registered in 2011 (0,09 mg/m3), when incidence of respiratory system diseases in this period (13103.2) exceeds the rates registered in 2012, 2013 and 2014 (12736.4, 11336.3, 13009.0 accordingly). There is no direct correlation between the morbidity rates of 0-15 year old children and SO2 concentration. Maximum incidence rate is registered in 2015 (48487.0) and in the same year is also registered maximum concentration of SO2 (0,14 mg/m3), whereas the lowest rate is registered in 2013 (35538,70), when SO2 concentration in 2013 is lower only by 0.02 mg/m3 compared to the concentration in 2015. Direct correlation between morbidity with asthma in children and concentration of SO2 was not identified. Prevalence of asthma is minimal in 2014 (65,4), maximal in 2012 (207,1), whereas SO2 concentration in 2014 (0,13 mg/m3) exceeds the concentration in 2012 (0,12 mg/m3). It has to be considered, that besides SO2 there are many small intensity adverse factors, which are also risk factors for development of respiratory diseases. Isolated action of these factors with certain concentrations may not demonstrate any adverse effects on human health, but the combined effect of their action is stronger and obviously will affect general health and specifically - respiratory system. Implementation of urgent measures for further improvement of their ambient air quality has been recommended, which will be the basis for minimizing of many chronic diseases.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1706
[Cu] Class update date: 170602
[Lr] Last revision date:170602
[St] Status:In-Process

  6 / 306246 MEDLINE  
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[PMID]: 28574350
[Au] Autor:Zawada T; Bierregaard L; Ringgaard E; Xu R; Guizzetti M; Levassort F; Certon D
[Ti] Title:Characterization of Kerfless Linear Arrays Based on PZT Thick Film.
[So] Source:IEEE Trans Ultrason Ferroelectr Freq Control;, 2017 May 26.
[Is] ISSN:1525-8955
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:Multi-element transducers enabling novel cost-effective fabrication of imaging arrays for medical applications have been presented earlier. Due to the favorable low lateral coupling of the screen-printed PZT, the elements can be defined by the top electrode pattern only, leading to a kerfless design with low cross-talk between the elements. The thick-film based linear arrays have proved to be compatible with a commercial ultrasonic scanner and to support linear array beamforming as well as phased array beamforming. The main objective of the presented work is to investigate the performance of the devices at the transducer level by extensive measurements of the test structures. The arrays have been characterized by several different measurement techniques. Firstly, electrical impedance measurements on several elements in air and liquid have been conducted in order to support material parameter identification using the KLM model. It has been found that electromechanical coupling is at the level of 35%. The arrays have also been characterized by a pulse-echo system. The measured sensitivity is around -60 dB, the fractional bandwidth is close to 60%, while the center frequency is about 12 MHz over the whole array. Finally, laser interferometry measurements have been conducted indicating very good displacement level as well as pressure. The in-depth characterization of the array structure has given insight into the performance parameters for the array based on PZT thick film and the obtained information will be used to optimize the key parameters for the next generation of cost-effective arrays based on piezoelectric thick film.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1706
[Cu] Class update date: 170602
[Lr] Last revision date:170602
[St] Status:Publisher
[do] DOI:10.1109/TUFFC.2017.2709253

  7 / 306246 MEDLINE  
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[PMID]: 28574314
[Au] Autor:Cleary DR; Siler DA; Whitney N; Selden NR
[Ad] Address:Department of Neurological Surgery, Oregon Health & Science University, Portland, Oregon; and.
[Ti] Title:A microcontroller-based simulation of dural venous sinus injury for neurosurgical training.
[So] Source:J Neurosurg;:1-7, 2017 Jun 02.
[Is] ISSN:1933-0693
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:OBJECTIVE Surgical simulation has the potential to supplement and enhance traditional resident training. However, the high cost of equipment and limited number of available scenarios have inhibited wider integration of simulation in neurosurgical education. In this study the authors provide initial validation of a novel, low-cost simulation platform that recreates the stress of surgery using a combination of hands-on, model-based, and computer elements. Trainee skill was quantified using multiple time and performance measures. The simulation was initially validated using trainees at the start of their intern year. METHODS The simulation recreates intraoperative superior sagittal sinus injury complicated by air embolism. The simulator model consists of 2 components: a reusable base and a disposable craniotomy pack. The simulator software is flexible and modular to allow adjustments in difficulty or the creation of entirely new clinical scenarios. The reusable simulator base incorporates a powerful microcomputer and multiple sensors and actuators to provide continuous feedback to the software controller, which in turn adjusts both the screen output and physical elements of the model. The disposable craniotomy pack incorporates 3D-printed sections of model skull and brain, as well as artificial dura that incorporates a model sagittal sinus. RESULTS Twelve participants at the 2015 Western Region Society of Neurological Surgeons postgraduate year 1 resident course ("boot camp") provided informed consent and enrolled in a study testing the prototype device. Each trainee was required to successfully create a bilateral parasagittal craniotomy, repair a dural sinus tear, and recognize and correct an air embolus. Participant stress was measured using a heart rate wrist monitor. After participation, each resident completed a 13-question categorical survey. CONCLUSIONS All trainee participants experienced tachycardia during the simulation, although the point in the simulation at which they experienced tachycardia varied. Survey results indicated that participants agreed the simulation was realistic, created stress, and was a useful tool in training neurosurgical residents. This simulator represents a novel, low-cost approach for hands-on training that effectively teaches and tests residents without risk of patient injury.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1706
[Cu] Class update date: 170602
[Lr] Last revision date:170602
[St] Status:Publisher
[do] DOI:10.3171/2016.12.JNS162165

  8 / 306246 MEDLINE  
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[PMID]: 28574247
[Au] Autor:Kanzaki M; Kawaguchi Y; Kawasaki H
[Ti] Title:Fabrication of Conductive Copper Films on Flexible Polymer Substrates by Low-temperature Sintering of Composite Cu Ink in Air.
[So] Source:ACS Appl Mater Interfaces;, 2017 Jun 02.
[Is] ISSN:1944-8252
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:The development of a thermal sintering method for Cu-based inks under an air atmosphere could greatly expand their application for printed electronics. However, it is well known that Cu-based inks cannot produce conductive Cu films when sintered at low temperatures in air because Cu readily oxidizes under such conditions. In this study, we have successfully demonstrated air atmosphere-sintering at low temperatures (less than 150 °C) via a simple hotplate heat treatment for producing conductive Cu films on flexible polymer substrates, using a novel Cu-based composite ink with sub-10 nm Cu nanoparticles protected with 1-amino-2-propanol with micron-sized Cu particles and submicron-sized Cu particles; oxalic acid was also added to prevent the oxidation of the Cu during sintering. The Cu films showed a minimum resistivity of 5.5 × 10-5 µΩcm when sintered in air at 150 °C for a very short period of 10 s. To the best of our knowledge, this is the first report of sintering of Cu-based inks in air at less than 150 °C. Another novel property of the present Cu-based composite ink is the lowest reported resistivity at 80 °C under N2 flow (5.3 × 10-5 µΩcm at 80 °C and 8.4 × 10-6 µΩcm at 120 °C). This fast, efficient, and inexpensive technology for thermal sintering in ambient air using composite inks could be a commercially viable method for fabricating printed electronics on flexible substrates.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1706
[Cu] Class update date: 170602
[Lr] Last revision date:170602
[St] Status:Publisher
[do] DOI:10.1021/acsami.7b04641

  9 / 306246 MEDLINE  
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[PMID]: 28574139
[Au] Autor:Guechi O; Lhuillier L; Houmad N; Goetz C; Ouamara N; Perone JM
[Ad] Address:Department of Ophthalmology, Metz-Thionville Regional Hospital Center, Mercy Hospital, Metz - France.
[Ti] Title:Visual outcomes following Descemet stripping automated endothelial keratoplasty for corneal endothelial dysfunction.
[So] Source:Eur J Ophthalmol;:0, 2017 Apr 10.
[Is] ISSN:1724-6016
[Cp] Country of publication:Italy
[La] Language:eng
[Ab] Abstract:OBJECTIVE: To assess objective and subjective visual outcomes achieved by patients with corneal endothelial dysfunction who have undergone surgical treatment with Descemet stripping automated endothelial keratoplasty (DSAEK). METHODS: A total of 40 eyes of 36 patients with corneal endothelial dysfunction underwent DSAEK. All were followed up for 1 year. Visual acuity (VA; logMAR), mean endothelial cell density (MCD; via noncontact specular microscopy), and topography assessment were performed at baseline (preoperatively). Visual acuity and topography measurement were repeated at postoperative year 1. Subjective assessment of visual quality was evaluated using the National Eye Institute Visual Function Questionnaire (NEI-VFQ). RESULTS: Preoperative best-corrected VA (BCVA) was 1.29 ± 0.53 logMAR with mean optical correction of -0.33 ± 1.74 D. Postoperative BCVA, assessed after a mean of 10.8 ± 2.1 months, showed mean line gain of 7.11 ± 4.8 logMAR, with optical correction of +1.17 ± 1.54 D. Mean 6-month postoperative pachymetry was 598.2 ± 72.3 µm. Three patients experienced premature graft detachment, requiring repositioning via injection of a sterile air bubble. No other adverse events were observed. Significant improvement (p<.05 for all) in general, near, and far vision, ocular pain, difficulty in carrying out daily tasks, dependency, social life, and mental health were reflected by NEI-VFQ scores at 10.4 ± 2.1 months postoperatively versus preoperatively. No significant correlation was noted between postoperative VA line gain and NEI-VFQ-25 questionnaire score (p>0.05). CONCLUSIONS: Descemet stripping automated endothelial keratoplasty treatment may restore corneal clarity, improve VA, and increase vision-related quality of life in patients with advanced endothelial dysfunction. Further large-scale study is needed to corroborate these findings.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1706
[Cu] Class update date: 170602
[Lr] Last revision date:170602
[St] Status:Publisher

  10 / 306246 MEDLINE  
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[PMID]: 28574103
[Au] Autor:Johagen D; Svenmarker P; Jonsson P; Svenmarker S
[Ad] Address:Department of Public Health and Clinical Medicine, Heart Centre, Umeå University, Umeå - Sweden.
[Ti] Title:A microscopic view of gaseous microbubbles passing a filter screen.
[So] Source:Int J Artif Organs;:0, 2017 May 23.
[Is] ISSN:1724-6040
[Cp] Country of publication:Italy
[La] Language:eng
[Ab] Abstract:PURPOSE: The aim of this study was to investigate the filtration efficacy of a 38-µm 1-layer screen filter based on Doppler registrations and video recordings of gaseous microbubbles (GME) observed in a microscope. METHODS: The relative filtration efficacy (RFE) was calculated from 20 (n = 20) sequential bursts of air introduced into the Plasmodex® primed test circuit. RESULTS: The main findings indicate that the RFE decreased (p = 0.00), with increasing flow rates (100-300 mL/min) through the filter screen. This reaction was most accentuated for GME below the size of 100 µm, where counts of GME paradoxically increased after filtration, indicating GME fragmentation. For GME sized between 100-250 µm, the RFE was constantly >60%, independently of the flow rate level. The video recording documenting the GME interactions with the screen filter confirmed the experimental findings. CONCLUSIONS: The 38-µm 1-layer screen filter investigated in this experimental setup was unable to trap gaseous microbubbles effectively, especially for GME below 100 µm in size and in conjunction with high flow rates.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1706
[Cu] Class update date: 170602
[Lr] Last revision date:170602
[St] Status:Publisher


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